1. Field of the Invention
The present invention relates generally to a force-resisting structure or support and, more particularly, to a force-resisting structure or support foldably constructed from one or more foldable blanks and especially suited for use as a pallet or dunnage support.
2. Brief Discussion of the Related Art
A pallet is primarily used to accommodate the mechanized bulk handling and transport of products. Typically, a pallet comprises a flat, elevated top surface for supporting a load, such as goods, containers, or packages, a sufficient distance above the ground or floor so that the fork of a forklift can be inserted under the top surface in order to move the pallet with the entire load thereon from place to place. Traditionally, most pallets have been made from pieces of wood, specifically soft wood, assembled with metal fasteners such as nails or screws. However, a number of problems face present day users of conventional wooden pallets. The rising cost of making and repairing wooden pallets has detracted from the overall cost effectiveness of palletized shipments. Wooden pallets are heavy, bulky and cumbersome, and empty wooden pallets require substantial storage space. It is especially costly to transport empty wooden pallets by rail or truck for reuse.
To save costs, conventional wooden pallets purchased and used by shippers are ordinarily returned to the shipper for reuse, but since wooden pallets are heavy, bulky and cumbersome, they are inconvenient to store and relatively expensive to return to the shipper. If the wooden pallet is not reused, it must be disposed of in a proper manner. Generally speaking, landfill or other waste disposal sites will not accept wooden pallets as is; rather, the pallets must first be reduced either by chipping or burning prior to disposal. Chipping adds significant cost to wooden pallet disposal, and burning wooden pallets is often precluded by environmental regulations.
In some instances, used wooden pallets can be retrieved by pallet recyclers. Recyclers who retrieve unwanted wooden pallets usually accept only certain sizes of wooden pallets and, most commonly, charge a fee for their retrieval. After repair or refurbishment, the recycler may attempt to resell the used wooden pallets. The market for recycled wooden pallets is limited, however, because many retailers refuse to receive goods transported on recycled wooden pallets due to the lack of any standards regulating the quality of the repair or refurbishment of used wooden pallets. Products shipped internationally on even new wooden pallets are faced with increasing regulations requiring various forms of chemical treatment to the wood to prevent infestation and transport of insects and parasites. Pallets constructed of plastic or metal have been proposed, but plastic and metal pallets have many of the same disadvantages as wooden pallets including being heavy, bulky and cumbersome, being costly and inconvenient to transport, store and dispose of, and being incompatible with environmental preservation. In view of the various drawbacks to pallets made from wood, plastic or metal, it would be desirable to construct a pallet from a material other than wood, plastic or metal, while maintaining many of the desirable characteristics generally associated with pallets made from wood, plastic and metal to provide a pallet that is lighter in weight, less expensive, strong, of simplified construction, easier and less costly to transport and store, that requires less space for storage, that is more readily recyclable or disposable, and that minimizes environmental impact.
A pallet constructed from a readily recyclable material such as corrugated paperboard would be especially desirable. In warehouses and retail stores, separate receptacles are commonly provided for collecting, compacting and/or storing recyclable materials, such as paperboard and plastics. The recyclable materials can then be retrieved, and oftentimes sold, and recycled into new materials and/or products. Corrugated paperboard, which is particularly conducive to being recycled, is typically formed as a layered structure or composite comprising a corrugated medium sandwiched between liner sheets. The corrugated medium forms a series of interconnected arches providing substantial structural strength. For example, a sheet of corrugated paperboard held in a vertical position can support a weight many times greater than its own weight.
Pallets made of corrugated paperboard have been proposed including pallets constructed from foldable corrugated paperboard blanks as represented by U.S. Pat. No. 6,029,582 to Ogilvie, Jr. et al. In many conventional corrugated paperboard pallets, the vertical supports for the elevated top surface of the pallet are secured with extraneous fasteners, including adhesive fasteners such as glue or mechanical fasteners such as staples or clips, and are not secured by the paperboard blanks themselves. Since an individual pallet ordinarily includes a plurality of vertical supports, the need to apply an extraneous fastener to each vertical support adds to the cost, time, labor and complexity involved in constructing or assembling the pallet. Furthermore, paperboard pallets in which the vertical supports are secured with extraneous fasteners are usually lacking in torsional strength. The extraneous fasteners also introduce undesirable materials into the pallet, and the fasteners may limit or complicate recyclability of the pallet. Some paperboard pallets rely on frictional securement of a top member of the pallet, which defines the elevated top surface, to a bottom member of the pallet, and such frictional securements lend little or no torsional support or strength to the overall pallet structure. Many conventional paperboard pallets do not have full perimeter support for the elevated top surface. Consequently, the force from a load carried on the elevated top surface can cause the elevated top surface to deflect in areas where the load is not directly supported by vertical supports of the pallet. Some conventional paperboard pallets cannot be foldably constructed or assembled from a single paperboard blank but, rather, require at least two foldable paperboard blanks that are assembled and then fastened together with extraneous fasteners. Some paperboard pallets attempt to duplicate the design of conventional wooden pallets, and these pallets are usually both heavy and expensive despite being made of paperboard.
Solid paperboard sheets known as slip-sheets are sometimes interposed between a load and a horizontal surface, such as the ground or floor, on which the load is supported. The slip-sheet is typically larger in peripheral size than the footprint of the load thereon thusly presenting an exposed marginal edge of the slip-sheet that can be grasped to slide the slip-sheet with the load thereon along the horizontal surface. Slip-sheets are not structurally or functionally similar to pallets.
A dunnage support is a type of packing conventionally utilized in transporting products. Conventional dunnage supports are ordinarily made of a foam material, and similar problems that arise with respect to the disposal of wooden, plastic and metal pallets also arise after the useful life of a dunnage support has ended. Additionally, the foam material of a conventional dunnage support can be prone to crumbling after a high impact, a characteristic that can lead to damage to both the dunnage support and the product being transported. The lack of a recycling program for foam both adds to the cost of dunnage supports and has caused various industries that utilize dunnage supports to look for dunnage supports that can be made of an alternate material to foam while still maintaining the positive characteristics associated with foam materials.
The need exists, therefore, for improved foldably constructed force-resisting structures or supports constructed from one or more foldable blanks, preferably corrugated paperboard blanks, and especially suited for use as a pallet or as a dunnage support.